Dry thunderstorms are thunderstorms that produce thunder and lightning, but the moisture generally evaporates before reaching the ground. Dry lightning can spark wildfires.
TAHOE, Calif. - Thunderstorms generally produce heavy rain, strong winds, hail and lightning. But this time of year, for the most part, weather makers moving into the Sierra Nevada are dry thunderstorms.
Dry thunderstorms are thunderstorms that produce thunder and lightning, but the moisture generally evaporates before reaching the ground. When there is precipitation, it either falls over higher elevations or is very scattered.
Lightning associated with dry thunderstorms can spark fires, especially when the conditions are on the ground are extremely dry.
"Sparks can smolder for a day or two," Cal Fire spokesman Daniel Berlant said. "We call these 'sleeper' fires."
Cal Fire sends reconnaissance planes to survey areas where there were lightning strikes to search for any signs of smoke or fires.
The biggest dry lightning outbreak occurred in Northern California late June into early July 2008. More than 2,000 fires burned from the coast to the Northern California mountains because of thousands of lightning strikes.
Even though dry lightning strikes are responsible for about only five percent of wildfires in the state, seven out of the top 20 largest fires in the state were caused by lightning, burning more than one million acres. The Rush Fire in Lassen County blackened more than 300,000 acres in California and Nevada in August 2012